CDH Series Push-Pull Dual-Dustproof Double-Acting Hollow Jack

The CDH series push-pull dual-dustproof double-acting hollow jack features a center-bore hollow plunger design that allows it to apply both compressive and tensile forces along the same axis, making it suitable for a broader range of loading scenarios than conventional solid-plunger jacks. The through-bore accepts tie rods, shafts, studs, cables, or other longitudinal elements that must pass through the jack body, enabling configurations such as strand jacking, bolt pre-loading through the jack axis, and column lifting with a center guide rod.

A dual-layer dustproof seal ring system on both the plunger and the rod provides enhanced contamination exclusion compared to single-seal designs, significantly extending seal service life in dusty or dirty operating environments. The precision guide ring eliminates piston-to-cylinder-wall contact under off-axis loading, protecting the bore from scoring. The baked-paint surface finish provides corrosion resistance for outdoor and industrial environments.

Active hydraulic retraction eliminates the speed and force limitations of gravity or spring return, enabling controlled piston withdrawal under load. Multiple mounting connection options including front and rear thread bosses, flange mounts, and clevis pins provide installation flexibility for diverse machine and structural configurations. NPT 3/8 quick-connect fittings, internal safety relief valve, and floating center tube — which extends service life by accommodating slight misalignment — are standard on all CDH models. Custom bore diameter, stroke, capacity, and end fitting configurations are available.